I'm using a First Sound Presence Deluxe II and recently replaced a Bryston 14B SST with a VAC Phi 110/110. The added gain in the system is phenomenal! I always felt I had to turn the volume pots up way too far on the First Sound to get the listening level I wanted with the Bryston. The VAC Phi 110/110 has balanced RCA inputs, and running single ended from the First Sound to the VAC's balanced RCA inputs gives me loads of volume at lower settings on the pots. I haven't tried the standard single ended inputs on the VAC yet, but I'd be willing to bet the volume bonus is still there over the Bryston. Bottom line, there seems to be great synergy between the First Sound and VAC. BTW, I'm using Von Schweikert VR4 SE loudspeakers.